[11.x] Improve Resend transport response handling (#54004)

Author: markovic-nikola

src/Illuminate/Mail/Transport/ResendTransport.php

@@ -4,6 +4,7 @@
 
 use Exception;
 use Resend\Contracts\Client;
+use Symfony\Component\HttpFoundation\Response;
 use Symfony\Component\Mailer\Envelope;
 use Symfony\Component\Mailer\Exception\TransportException;
 use Symfony\Component\Mailer\SentMessage;
@@ -97,6 +98,8 @@ protected function doSend(SentMessage $message): void
                 'text' => $email->getTextBody(),
                 'attachments' => $attachments,
             ]);
+
+            throw_if($result['statusCode'] != Response::HTTP_OK, Exception::class, $result['message']);
         } catch (Exception $exception) {
             throw new TransportException(
                 sprintf('Request to Resend API failed. Reason: %s.', $exception->getMessage()),